An LED bulb comprises a structural shell formed by folding a flat PCB into a three-dimensional polyhedron shape and a fitting for removably coupling the bulb to a light socket. The PCB comprises a plurality of LEDs, at least one LED mounted electronically on a plurality of faces of the polyhedron, and a driver circuit for driving each LED. The perimeter of the PCB is shaped to join adjacent faces. Each LED produces minimal excess heat, which is partially conducted by a metallic heat sink bridge to the PCB and dissipated to the air through the PCB and through a plurality of spaces in the shell.